Enadenotucirev (EnAd; formerly called ColoAd1) is a chimeric oncolytic adenovirus with fibre, penton and hexon from Ad11p. It was created by a bioselection process, WO2005/118825, and has a chimeric E2B region. EnAd is currently in development for the treatment of colorectal cancer and it appears to selectively elicit necrotic death of colon cancer cells in vivo.
The advantageous properties of EnAd were thought to be primarily attributable to the chimeric E2B region. However, the present inventors believe that some of the advantageous properties of EnAd, for example the ability of an infected cell to produce intact new virus particles and to selectively induce necrosis of cancer cells is due at least in part to the E4orf4 deletion.
The present inventors believe this significant insight can be employed to genetically engineer alternative oncolytic viruses and viral vectors.